Manufacture of stabilized metaldehyde



Patented June 7, 1927.

UNITED STATES- "PATENTi orr ca.

:ainn Lflsonnn, or IBASEL, swrrzaaLnm, ABSIGNOR To THE socm rY npnx'rmzrrA'rswaax LONZA, or GAMPEL AND BASEL, SWITZERLAND.

MANUFACTURE OF STABILIZED META LDEHYDE.

Io Drawing. Application filed June 26, 1922, Serial Io. 571,041, and in Germany December .8, 1981."

According to the U. S. Letters-Patent No.

- 1,432,387, dated October 17, 1922, metalde-' hyde can be rendered more stable at high temperatures by eliminating the residual traces which it contains of the catalyzer used in preparing the metaldehyde, or by depnving the catalyzer of the o portunlty of com ing into action, for examp .e by transformin the catalyzer, either chemically, or physica ly, into an inactive condition. I. I have now ascertained, that ammonium carbonate is particularly suitable for the aforesaid purpose, and that the employment of ammonium carbonate as a stabilizing agent is attended by the further considerable advantage that. by regulating the amount of stabilizing agent added, fuel bodies of variousidegrees of stability can be obtained -from metaldehyde. a

For exampleit has been found that, al-

though the purest metaldehyde is better adapted than less purposes for whic 1 it is desired to employ It as a fuel, already on account of its greater stability at-high temperatures), above centigrade, and its consequent more favorable behaviour during transport in hot climates, the less pure metaldehyde possesses also advantages for other purposes b reason of its greater inflammability, and t e more vividflame it gives in burning, and also because the purest metaldehyde, when the flame is extinguished, becomes covered with a sligh'tdown of met-aldehyde crystals wh ch may be a cause of troublein mechanically sensitive burners, for example, in pocket apparatuscs in which .the metaldehyde is pushed forward, in proport on asit burns away. for the purpose of obtaining a' uniformly burning flame. I a

The ammoniumcarbonate is mixed with the metaldehyde powder before the compression,'in a quantity corresponding to the de' .ing ascertained by weighing. I

pure metaldehyde for 'most gree of stability des red. Owing to the volatilityof the ammonium-carbonate, there is no danger of obtaining a not uniform mixture, which otherwise would occur with such feeble addition.

shown y the following experiments:

Large pressed blocks of metaldehyde were kept, for 16 days, in succession at a constant temperature of 30 (1,, the loss in weight be- The losses amounted to: 12 per cent with a block of metaldehyde preparedfin the ordinary way,

- 3,5 per cent with a block. of metaldehyde containing i of ammonium carbonate,

2 per cent with a .block of metaldehyde containingfi of ammonium parbonate,

1,5 per cent with a block of-metaldehyde 3 containing W666 of ammonium carbonate.

The action of ammon um carbonate on the stabllit of the fuel bodies thus produced is In all, cases it becomes possible to impart to metaldehyde the degreeof stability most suitable for the particular purposes for which it is to be employed.

What I claim is: a .1. A process of stabilizing metaldehyde pnsisting in mixing it with ammonium carb'onate.

2. A process for obtaining metaldehyde of various degreesv of stability consisting in mixingit with a quantity of ammonium carbonate varying with the desired degree of stability. L

3. As a new article of manufacture, sta- EMIIL LI'J'soHER. 

